Toxicology (main): Difference between revisions
| Line 82: | Line 82: | ||
*E thanol or other alcohols | *E thanol or other alcohols | ||
*D igoxin, digitalis | *D igoxin, digitalis | ||
===Seizures=== | |||
OTIS CAMPBELL | |||
*[[Organophosphates]], oral hypoglycemics | |||
*[[TCA]], [[theophylline]], tramadol | |||
*Isoniazid, Insulin | |||
*[[Sympathomimetics]], [[salicylates]], strychnine | |||
*Camphor, [[carbon monoxide]], [[cyanide]], chlorinated hydrocarbons, [[cocaine]] | |||
*[[Anticholinergics]] (antihistamines), amphetamines, antidepressants (citalopram, TCAs, buproprion) | |||
*[[Methanol]], Methylxanthines (theophylline, caffeine), [[MAOI]] | |||
*[[PCP]], propranolol | |||
*Benzo withdrawal, buproprion, botanicals (hemlock, nicotine), GHB | |||
*EtOH withdrawal, ethylene glycol | |||
*[[Lead]], [[lithium]] | |||
*Lidocaine, lindane (pesticide, scabies) | |||
==Evaluation== | ==Evaluation== | ||
Revision as of 03:27, 26 March 2019
Background
Epidemiology
- In 2014, ~2.2million human exposures reported to US poison control centers
- Top 5 substance classes:
- analgesics (11%)
- cosmetics/personal care products (8%)
- household cleaning substances (8%)
- sedatives/hypnotics/antipsychotics (6%)
- antidepressants (4%)
- 1,835 human exposures resulted in death
Autonomic Nervous System Receptors and Their Effects
- Parasympathetic - ACh is transm
- Muscarinic
- receptors in heart, eye, lung, GI, skin and sweat glands
- Bradycardia
- Miosis
- Bronchorrhea / Bronchospasm
- Hyperperistalsis (SLUDGE)
- Sweating
- Vasodilation
- Nicotinic
- receptors in both sympathetic and parasympathetic nervous systems
- fasciculations, flaccid paralysis
- ?Mild bradycardia, hypotension
- Muscarinic
- Sympathetic
- Alpha effects (vessels, eye, skin)
- Mydriasis, hypertension, sweating
- Beta effects (heart, lungs)
- Tachycardia, bronchodilation
- Alpha effects (vessels, eye, skin)
Clinical Features
Toxidrome Chart
| Finding | Cholinergic | Anticholinergic | Sympathomimetic | Sympatholytic^ | Sedative/Hypnotic |
| Example | Organophosphates | TCAs | Cocaine | Clonidine | ETOH |
| Temp | Nl | Nl / ↑ | Nl / ↑ | Nl / ↓ | Nl / ↓ |
| RR | Variable | Nl / ↓ | Variable | Nl / ↓ | Nl / ↓ |
| HR | Variable | ↑ | ↑ (sig) | Nl / ↓ | Nl / ↓ |
| BP | ↑ | ↑ | ↑ | Nl / ↓ | Nl / ↓ |
| LOC | Nl / Lethargic | Nl, agitated, psychotic, comatose | Nl, agitated, psychotic | Nl, Lethargic, or Comatose | Nl, Lethargic, or Comatose |
| Pupils | Variable | Mydriatic | Mydriatic | Nl / Miotic | |
| Motor | Fasciculations, Flacid Paralysis | Nl | Nl / Agitated | Nl | |
| Skin | Sweating (sig) | Hot, dry | Sweating | Dry | |
| Lungs | Bronchospasm / rhinorrhea | Nl | Nl | Nl | |
| Bowel Sounds | Hyperactive (SLUDGE) | ↓ / Absent | Nl / ↓ | Nl / ↓ |
- ^Consider Sympatholytic when looking at Sedative OD or someone who doesn't respond to Narcan
- Withdrawal from substances have the opposite effect
Differential Diagnosis for Specific Signs
Hyperthermia
- Altered Metabolism
- Aspirin (Salicylate) Toxicity
- withdrawal states
- thyroid hormones
- dinitrophenols
- Increased Muscle Activity
- withdrawal, sympathomimetics
- MAOI Toxicity
- PCP, LSD
- Lithium
- Amoxapine
- Serotonin Syndrome
- Impaired Heat Dissipation
- anticholinergics
- antihistamines
- antipsychotics (TCAs)
- Malignant Hyperthermia
- anesthestics
- Neuroleptic Malignant Syndrome
- phenothiazines, Lithium, LevoDopa
Hypothermia
- Exposure
- Ethanol Toxicity
- Sedative hypnotics
- Opioids
- TCAs
- Phenothiazines
- Insulin (Hypoglycemia)
Increased Respiratory Rate
- Direct Stimulation
- Aspirin (Salicylate) Toxicity
- Metabolic Acidosis
- dintirophenol, pentachlorophenol
- hepatorenal failure
- CNS stimulants (cocaine, amphet, theophylline)
- Tissue Hypoxia
Respiratory Depression
- Central Depression
- antipsychotics
- Chlorinated hydrocarbons
- Sedative/Hypnotics (Ethanol Toxicity, glycols)
- Tricyclic (TCA) Toxicity
- Lomitil
- Muscle Failure
- Organophosphates
- Marine Toxins
- Nicotine
- strychnine
- botulinis
- Mojave rattlesnake, Cobra
Bradycardia
- P ropranolol/ beta-blockers, poppies (opiates), propoxyphene,
physostigmine
- A nticholinesterases, antiarrhythmics
- C lonidine, calcium channel blockers
- E thanol or other alcohols
- D igoxin, digitalis
Seizures
OTIS CAMPBELL
- Organophosphates, oral hypoglycemics
- TCA, theophylline, tramadol
- Isoniazid, Insulin
- Sympathomimetics, salicylates, strychnine
- Camphor, carbon monoxide, cyanide, chlorinated hydrocarbons, cocaine
- Anticholinergics (antihistamines), amphetamines, antidepressants (citalopram, TCAs, buproprion)
- Methanol, Methylxanthines (theophylline, caffeine), MAOI
- PCP, propranolol
- Benzo withdrawal, buproprion, botanicals (hemlock, nicotine), GHB
- EtOH withdrawal, ethylene glycol
- Lead, lithium
- Lidocaine, lindane (pesticide, scabies)
Evaluation
Toxicological Exam
- All vital signs (Temp, RR, HR, BP)
- Neurologic exam
- Level of consciousness
- Pupillary exam
- Motor response
- DTRs
- Skin Exam - moisture, temp
- Lung Exam
- Bowel Sounds
- ECG (ie. look for QT prolongation, QRS prolongation, etc)
Management
- Depends on agent
- See antidotes
- "Coma cocktail" when suspecting toxic ingestion (mnemonic = "DONT")
- Dextrose (50mg IV)
- Oxygen
- Naloxone (0.2-0.4mg IV/IM, repeat dose 1-2mg)
- Empiric opioid ingestion treatment
- Thiamine (50-100mg)
- Treat or avoid Wernicke encephalopathy
- Though some suggest giving thiamine prior to dextrose, do NOT let this delay treatment of hypoglycemia!
- Case reports of dextrose precipitating Wernicke's involved thiamine-deficient patients receiving prolonged course of IV glucose, NOT with single bolus[1][2]
Disposition
- Depends on agent